This invention relates generally to online systems, and more specifically to presenting content to an online system user.
Online systems, such as social networking systems, allow users to connect to and communicate with other users of the online system. Users create profiles on an online system that are tied to their identities and include information about the users, such as interests and demographic information. The users may be individuals or entities such as corporations or charities. Because of the increasing popularity of online systems, and the significant amount of user-specific information maintained by online systems, an online system allows users to easily communicate information about themselves to other users and share content with other users. For example, an online photo and video sharing system generates content feeds for presenting photos and videos uploaded by its users to other users. In addition to photos and videos, other types of content uploaded and shared by online system users may be presented, such as stories describing actions performed by online system users, status updates, event announcements, activity invitations, location check-ins, or any other suitable information.
Additionally, entities may sponsor presentation of content items via an online system to gain public attention for the entity's products or services, or to persuade online system users to take an action regarding the entity's products or services. Many online systems receive compensation from an entity for presenting online system users with certain types of sponsored content items provided by the entity. Frequently, online systems charge an entity for each presentation of sponsored content to an online system user (e.g., each “impression” of the sponsored content) or for each interaction with sponsored content by an online system user (e.g., each “conversion”). For example, an online system receives compensation from an entity each time a content item provided by the entity is displayed to a user on the online system or each time a user is presented with a content item on the online system and the user interacts with the content item (e.g., requests additional content by interacting with the content item).
Online systems commonly present their users with feeds of content that include sponsored content items and content items selected for presentation to a user by the online system. As users of online systems more frequently access content via mobile devices or other devices with a limited display area, an online system may combine multiple content items into a scrollable content unit to reduce the display area in which content is presented without reducing the amount of content presented. A user may view alternative content items included in a scrollable content unit by interacting with the scrollable content unit. For example, a feed of content presented on a mobile device may include a scrollable content unit that displays a content item to a user and includes multiple alternative content items that are presented if the user interacts with the scrollable content unit (e.g., by swiping a screen of a display device presenting the scrollable content unit with a finger or stylus). This allows an online system to present multiple content items to a user in a minimally obtrusive manner and increases the number of content items capable of presentation to the user.
Although users may view alternative content items included in a scrollable content unit by interacting with the scrollable content unit, online systems may lose opportunities to present content to a user if the user stops interacting with the scrollable content unit before all of the content items included in the scrollable content unit have been presented. For example, if a user navigates away from a scrollable content unit without interacting with the scrollable content unit, the online system loses the opportunity to present alternative content items included in the scrollable content unit that would have been presented if the user interacted with the scrollable content unit. This may decrease potential revenue for an online system, such as revenue received from one or more entities in exchange for presenting sponsored content items to a user of the online system. Revenue to the online system may be further decreased if the online system would also earn revenue from interactions by the user with content items in the scrollable content unit that were not presented. While an online system may attempt to recapture these lost opportunities by repeatedly presenting a scrollable content unit at various times, repetitive delivery of the same content may frustrate users and decrease user interaction with the online system, resulting in further loss of potential revenue.